Cut-off for steam-engines



(No Model.) I

F. A. MILLER. GUT-OFF FOR STEAM ENGINES.

N0.497,s32. Patented May16,1893.

WfiTLESsES: ZL BLUE/12:11 v. M (/ik w Z) UNITED STATES PATENT OFF CE.

FRANK A. MILLER, OF JOLIET, ILLINOIS.

CUT-OFF FOR STEAM-ENGINES.

SPECIFICATION forming part of Letters Patent No. 497,332, dated May 16, 1893.

Application filed January 19, 1893- Serial No. 458,939. (No model.)

To all whom it may concern:

Be it known that I, FRANK A. MILLER, a citizen of the United States of America, residing at Joliet, in the county of Will and State of Illinois, have inventedpertain new and useful Improvements in Automatic Out-Offs for Steam-Engines, of which the following is a specification, reference being had therein to the accompanying drawings and the letters of reference thereon, forming a part of this specification, in which- Figure l is a side elevation of the automatic cut off shown as being applied to the side of a four valve steam cylinder. Fig. 2 is a perspective view of one of the trips. Fig.

3 is a side view of a section of one of the rods for connecting one of the upper valve shafts with one of the trips, and showing its forked end for carrying oneof the trips, and Fig. 4: is a plan View of the automatic cut off showing it attached to a section of the cylinder.

This invention relates to certain improvements in automatic cut-offs for steam engines, and is intended to be applied to the side of a four valve steam cylinder, which improvements are fully set forth and explained in the following specification and claims.

Referring to the drawings A represents an ordinary steam cylinder provided with two inlet valves in its upper part, and two exhaust valves in its lower part, and having an ordinary wrist plate It journaled on a pin on the side of the cylinder in the ordinary manner, and shown in broken lines in Fig. 1. and

.in full lines in Fig. 4. The cranks L of the lower valve shafts are connected to said wrist plate by means of the rods B in the ordinary manner so that oscillation of said wrist plate will cause the lower exhaust valves to be alternately opened and closed, the said wrist plate being oscillated by means of an eccentric rod a seated on a wrist pin 0 on the outer face of said wrist plate. Said wrist plate has pivotally connected to it on its inner side the two trips T T having hooks V, which trips are inclosed respectivelyin the forked inner ends D of the rods B, that are pivotally connected at their outer ends to the cranks 7c of the inlet valve shafts. The upper inner sides of the said forks D are lined with a steel plate V which may be replaced when worn, and which forms the offset m on its inner end for the hooks V of the trips T to catch over alternately as the wrist plate oscillates. The lower inner sides of said forks are provided with a tongue S having its outer end pivotally connected at z'to the outer end of the lower tine of the fork, and having itsinner end resting upon a post P which passes through the lower tine of the fork and stands upon the outer end of a spring S, which spring S is intended to be strong enough to cause the trip that is between plate V and tongue S, to be kept in close contact with said plate V so as to cause the hook V of the trip to hook over the offset m whenever the wrist plate moves the trip back to the inner end of said fork.

O. O. are a pair of arms pivotally attached at their lower ends to the side of the cylinder, one at either side of the pin upon which the wrist plate R is journaled, on a boss H.

These arms are respectively connected to the arm N also pivotally attached to the side of the cylinder, and betweemarins O. and connected with said arms by means of the rods Z and in such manner that when arm N is oscillated through the medium of rod F connecting its upper end with the governor, the upper ends of arms 0 will be oscillated to or fromeach other in the arc of a circle. The upper ends of arms 0 are provided with laterally extending projections no". extending toward the inner side of the wrist plate and directly over a cam flange W on the inner side of thet-rips T shown particularly in Fig. 2, so that said cam flange may engage said projections when.the wrist plate oscillates so as to bring them in contact with each other,

for the purpose of disengaging the hook V of the trip from offset m of forked rod B, D. The oscillation of arms 0 to and from each other will elevate and lower the projections or stops 1" so as to cause them to be engaged sooner or later by the trips T and cause steam to the cylinder to be cutoff sooner or later according to the speed of the engine.

In operation the wrist plate is shown in Fig. 1 as being about to be oscillated in the direction shown by the arrow, and as the trip at the head end of the cylinder is shown connected with the rod B and offset m by means of the engagement with it of hook V on said trip, said rod and the crank will be carried with the wrist plate and trip until the cam flange W of the trip engages the projection or stop 7' on the upper end of arm 0, which Will cause said trip to be disengaged from the offset m, when the dash pot mechanism G connected to said crank 70 will cause the valve attached to it to be instantly closed; but before said trip becomes so disengaged the wrist plate has oscillated far enough so that the opposite trip T toward the crank end of the cylinder has moved far enough forward to ward that end of the cylinder to have its hook V engage the offset m of the valve rod B toward that end of the cylinder, at which time the wrist plate is oscillated in the opposite direction from the arrow until the said trip is released from its rod by means of its engage ment with the opposite projection or stop 1' and permit the dash pot mechanism G at the crank end of the cylinder to close its valve in the same manner as the opposite valve was closed, so that the two inlet valves are opened and closed by means of the oscillating Wrist plate R through the medium of said trips and their rods, and the stops for engaging said trips, and steam is cut off earlier or later as said projections or stops 7' are elevated and lowered to and from each other by means of the governor rod F through the medium of said arms 0, and N and rods ,2.

Having thus described my invention, What I claim as new, and desire to secure by Letters Patent, is as follows, to wit:

1. In an automatic cut off for steam engines the combination of the oscillating wrist plate R, trips '1 pivotall y connected thereto and having the hooks V and cam flange \V, rods B pivotally connected at their outer ends with the cranks of the inlet valves, and having the forked inner ends D for carrying said trips, and having the offsets m for engaging the hooks of said trips, hinged tongue S, spring S, post P, oscillating arms 0 having the pro- 3' ectin g stops 1', and the means for oscillating said arms and wrist plate, all arranged to operate substantially as and for the purpose set forth.

2. In an automatic cut ofii for steam engines the combination of the oscillating wrist plate R, trips T pivotally connected thereto and having the hooks V, rods B pivotally connected to the cranks 7c of the inlet valves, and having forked inner ends D for carrying said trips, and having the offsets m for engaging said trip hooks, and the springs for causing such engagement, the adjacent adjustable stops 9" for alternately engaging said trips, the dash pot mechanism G, rods 15 for connecting said wrist plate and cranks L- of the exhaust valves and the means for oscil- 'latin g said Wrist plate and stops substantially as and for the purpose set forth.

3. In an automatic cut off for steam engines, the combination of an oscillating wrist plate, a pair of trip hooks pivotally connected thereto, a pair of rods having their inner ends forked for receiving said trip hooks and having their outer ends pivotally connected to the cranks of the inlet valves, adjustable stops for engaging said trip hooks for alternatel y releasing them from said rods, and the means for oscillating said Wrist plate and for adjusting said stops substantially as and for the purpose set forth.

FRANK A. MILLER.

Witnesses:

THOS. II. IIUToHINs, J. E. MILLER. 

